Dangers from Ground Level Ozone
Although the ozone layer provides vital protection for our planet, ozone at ground level is a pollutant and can cause serious health problems.
In most developed countries, its levels are now constantly monitored and most local authorities in the UK now record ozone levels as part of their work in measuring air quality.
Respiratory ProblemsDoctors believe that even fairly low levels of ozone in the air can aggravate the symptoms of a number of conditions such as asthma.
In 2003, a heatwave in Europe led to a record number of days when ozone pollution was severe and experts believe that ozone exposure contributes to thousands of premature deaths in Europe every year.
In the USA, a research project carried out in 2003 revealed that long term exposure to ozone and other fine particles in the air can damage tissue in the lungs and airways – causing additional asthma attacks in sufferers and making breathing more difficult for people with respiratory disorders.
High levels of ozone can also irritate the eyes, leading to soreness.
Children Most at RiskThe researchers said children are especially vulnerable to ozone exposure because their respiratory systems are not yet fully developed and usually they spend more time outdoors than adults.
They concluded that ground level ozone can have a severe effect on asthmatic children even when levels are below the current legal standards in America.
Research in BritainIn 2008, the UK government launched a new research project to examine rural air pollution resulting from ground level ozone, heavy metals and the burning of fossil fuels.
Amongst other things, it is designed to check the effect that ozone had on the atmosphere and eco systems between1980 and 2005 and, if possible, to assess the causes.
Rural Air AffectedIt’s natural to assume that people living in cities are more at risk from ground level ozone but in fact, ozone concentrations tend to be lower in cities than in the countryside close to cities because traffic fumes – which are higher in cities – release nitric oxide which attacks ozone.
Most ozone at ground level is formed by a reaction between oxygen, nitrogen dioxide and Volatile Organic Compounds (VOCs) in the presence of sunlight.
Other EffectsWhen ground level ozone levels are high, it can cause damage to crops, plants and materials such as rubber, as well as causing health problems. After being formed, it lives in the air for around 20 minutes depending on the temperature.
Ozone is classified as one of the greenhouse gases and higher concentrations at ground level could accelerate global warming but because it exists for only a short time, it doesn’t build up in the same way as other greenhouse gases.
Southern EnglandIt is one of eight main pollutants included in the UK’s Air Quality Strategy and in 2006, a local authority in the south of England reported summer-time levels of ozone were becoming a problem throughout the south of England.
A website with details of UK air pollution is now maintained on behalf of the government and it is possible to check the levels of ozone pollution in different regions.
Currently, rural ozone levels in Europe are treble that of those that existed in the pre-industrial era but they have been declining in recent years, due mainly to new European laws on air pollution and the fitting of catalytic converters to cars.